Stock standard transmissions have a couple of things going against them that make them the wrong choice for use as drag race transmissions. Firstly they just aren’t designed to handle the amount of torque and horsepower your drag racing engine produces.
The second problem is that the gearing, it is not set to handle the acceleration changes required. Most stock transmissions are made to casually accelerate to either street speeds or highway speeds in order to save on fuel consumption. However if you are trying to make a sub-ten second pass on the drag strip, fuel economy will be the least of your worries. You want your engine to rev to the max torque output as quickly as possible and then hold that max torque output for those few important seconds as you successfully engage and shift gears, and then do it again without having your transmission fall to peices. You cnnot successfully use a stock transmission in a race car.
Without a drag race transmission, your engine has to work doubly hard or harder in getting up to speed and then maintaining it. Your engine runs most efficiently when it’s operating around the middle of the RPM range. Horsepower and torque output are at their lowest at low RPM, and they start dropping off quickly at the higher end of the RPM range. The gearing in the transmission allows you to keep your engine working in the optimum RPM band.
Our choices for race transmissions are the GM Powerglide , Ford C4 , Ford C10 and Mopar Torqueflite series of performance transmissions.
